The present invention relates to a coupler for connecting the service port of a system containing refrigeration fluid to an exit conduit.
Regulations of the U.S. Environmental Protection Agency (EPA) now mandate the use of difluoromethane, a refrigerant known as R-134A, or HFC-134, in place of dichlorodifluoromethane, known as Freon 12 or R-12. Even though this new refrigerant is believed to minimize ozone depletion, it nevertheless may not be released into the atmosphere but must be removed, collected, and recycled in a closed system.
Refrigerant fluid typically is removed through one or more service ports directly before or after the compressor stage of a refrigeration system. Conventional fittings, adapters and couplings have been used for connecting and disconnecting recycling machines to the tubular high or low-side service ports of air conditioning systems. Recently the Society of Automotive Engineers, EPA, and automotive manufacturers have recommended that service ports of automotive air conditioners be provided with special quick connect/disconnect ports which prevent refrigerant from escaping into the atmosphere. In order to comply with this requirement, manufacturers have begun to make couplings and fittings to comply with the requirements of the SAE, EPA and auto manufacturers.
U.S. Pat. Nos. 4,667,925; 4,756,558; 4,913,467; 5,046,523 and 5,069,424 describe typical devices. Common assigned U.S. Pat. No. 5,244,010, the contents of which are incorporated herein by reference, describes an improved coupler for refrigeration systems which seals the connection between a service port and the coupler before the apparatus is in a snap-on and lock mode, thereby making it safe and environmentally sound. The referenced device locks the connection through a snapping action while the coupling operation is in progress. Moreover, the referenced device is light, easy to use, and relatively small, so that it can be used in confined spaces such as in an automobile engine compartment, and can be disconnected quickly with an absolute minimum of refrigerant leakage.
Because the service port is used for both introducing and removing refrigeration fluids, it is desirable if the coupling device can accommodate a variety of conduits at the exit port, as for example those used for recycling refrigeration fluids and those used for introducing fresh (or recycled) refrigeration fluids, and to do so while the coupler is locked on the service port of the refrigeration unit. It also is desirable to have better control of the flow of refrigerant and to increase safety. To accomplish these ends, the device should be capable of being sealable (so as to prevent loss of fluid while changing conduits) while also preventing loss when the coupler is removed, either intentionally or accidentally, from the service port of the refrigeration system.